Lexmark 10B041K Black Return Program Print Cartridge for use with C750. Page yield 6,000. For outstanding print quality from your Lexmark C750 laser printer, choose a genuine Lexmark Return Program Laser Toner Cartridge (10B041K). Keep a spare black cartridge on hand for when you see a '88 Black Toner Low' error message. When print quality is no longer satisfactory, you can quickly swap in a fresh cartridge to keep printing straight away. This economically-priced cartridge comes packed with enough toner to print 6,000 pages.